And I'm Melissa Block. Those tuning in to President Obama's weekly radio address tomorrow will instead hear the voice of Francine Wheeler. Her 6-year-old son, Ben, was among those shot and killed at Sandy Hook Elementary School in December. And the White House made the highly unusual decision to turn the microphone over to her. In this administration, only the president and vice president have delivered the address before.

Ms. Wheeler's message comes as the Senate is about to begin debate on gun control legislation. And that's where we begin our weekly chat with political commentators E.J. Dionne of The Washington Post and David Brooks of the New York Times. Hi to you both.

E.J. DIONNE: Good to be here.

DAVID BROOKS: Good to be here.

BLOCK: The bipartisan Senate compromise on guns that was announced this week, reached by Democrat Joe Manchin and Republican Pat Toomey, pretty much boils down to this, expanding background checks to all commercial sales. They've now proceeded to debate, but there's no assurance that this measure's going to pass in the Senate, much less get through the house. David, what do you think the likelihood is that a gun bill makes it out of Congress?

BROOKS: I put it at more than 50/50. I think the Senate's going to get a decent majority on this and it's got some other things they're working on, the mental health aspects, increased community mental health clinics, other things like that, some of the laws on gun trafficking. And you get the sense that there's a significant number of Republicans. Now, I spoke to a senior member of the House this week who was, you know, more cautious, but acknowledged that if there's a big Senate majority, it becomes hard for the House to be the one saying no.

And I think it's slightly better than 50/50 this will pass.

BLOCK: Well, E.J., I read a scorching editorial yesterday in the New York Daily News which called this gun compromise a smashing victory for the NRA - no assault weapons ban, no ban on high capacity magazines. Four months after Newtown, the paper said, Washington has added the hope of a caring nation to the roster of casualties. What do you make of that argument?

DIONNE: You know, I think sometimes in politics you have to be able to keep two contradictory ideas in your head at the same time. On the one hand, I agree with the thrust of that editorial that this alone is not enough. There should be more that's happening. There will probably be some other good elements of this bill, though I do think a bill that doesn't at least ban the high capacity magazines, it'll be a shame if that doesn't pass.

But, and here's the but, we have not had any gun control legislation since 1994. The fact that we have gotten this far, the fact that you had the deal between Joe Manchin and Pat Toomey, the fact that 16 Republicans voted not to shut down debate on this, I think it says we're moving forward. And so I think there are, you know, the old phrase is don't mourn, organize.

I think this time the phrase should be celebrate and keep organizing because I think those families made a huge difference and I think the country, something snapped in the country after the Newtown killings and we said, no, we're not going to just sit there and do nothing yet again.

BLOCK: Well, there was more bipartisan deal-making this week on immigration, a comprehensive bill is expected to come out early next week. And Republican Marco Rubio of Florida, apparently, will be leading the charge to promote it. He had been lukewarm before, but this weekend, he's hitting seven Sunday talk shows. Apparently, he is all in. David, where do you see him positioning himself on this?

BROOKS: Hitting seven shows is not all in. That's like breathing for politicians, like their fantasy life.

DIONNE: I'm looking for the Food Channel and ESPN.

BLOCK: MTV are you in?

BROOKS: This is actually just functionalism breaking out in Washington. I'm impressed by what they've done. This gang of eight senators, most gangs fail, but they've come up with something, which is not only an immigration bill and not only watered down the way, frankly, the gun bill is, this is a pretty robust bill. It's robust on the security enforcement. It's robust on getting a pathway to some sort of normalization for the people who are here.

And it's very robust on getting more merit-based systems, so we're attracting the high school workers. I think they've just done a fantastic job and it's really a testimony given how often this has failed before. And here's a case where I'm more optimistic.

BLOCK: David likes it. E.J., what about you?

DIONNE: Yeah, no, I think it's a great step forward. It's got a path to - the key thing is we're going let people become citizens eventually. And I think what this shows is what a difference elections can make in a democracy. I think the Republican Party changed its position, became much less oppositional to immigration reform when they saw that Mitt Romney got 27 percent of the Latino vote. They know they cannot win elections if that's the highest share they can get of Latinos.

So I think the Republicans are doing the right thing for pragmatic reasons and that doesn't bother me.

BLOCK: Well, this week, President Obama also released his budget. David, he's calling it his final offer. He wasn't able to get a deal with Republicans the last time he tried this, why should he think it would work this time?

BROOKS: There will be about three or four more final offers before we're done. I think the bottom line on this budget is Obama did some moderately brave things. He upset the liberals. He moved to the center. He said you got to build a center out majority so I think he deserves some credit. Nonetheless, it is still fundamentally true this budget doesn't alter the landscape we're on, the trajectory we're on, which is a lot more money for senior citizens and those programs and a lot less money for everybody else.

So domestic discretionary spending, which is all that stuff that goes into Welfare, education, that's going down to levels not seen since the Eisenhower administration. And that's fundamentally the squeeze we're in these days and this doesn't reverse that.

BLOCK: And E.J., interesting that House Budget Committee chairman Paul Ryan told NPR yesterday this is the first time in this presidency that I have seen a chance at a bipartisan budget agreement. I'm cautiously optimistic about that.

DIONNE: You know, Ryan has said a number of different things on different days about this, so we will see if that's true. I applaud David for going to the left and saying we need more discretionary spending. I think the fear on the Democratic side is that here goes Obama again negotiating with himself. He calls for changing the index for Social Security.

I know a lot of Democrats who, if that were part of a big deal that really did have a lot of new revenues, they might be able to go along with it. They are very worried that this is just the opening bid. The White House says, no, we're going to be tough. This is our only offer. You know, this is as far as we're going to go. But that's not how negotiations work. So I think it's a real test of whether the reappearance of the old Obama can work in this circumstance in a way that it didn't work a couple years ago.

BLOCK: Well, good to have both here on our last day in our old building before we move. Thanks for coming in.

DIONNE: Thank you.

BROOKS: See you.

BLOCK: E.J. Dionne of The Washington Post and David Brooks of the New York Times. Transcript provided by NPR, Copyright NPR.